1. Field of the Invention
This invention relates generally to a voice messaging system. More particularly, it relates to transcription of a voice message into a text file and transmission of the same to a remote location.
2. Description of Related Art
Today, many people use a digital or tape answering machine or voice mail system to receive and play back voice messages. A digital answering machine stores messages in solid state memory. A tape answering machine stores messages on magnetic tape. A voice messaging system is typically used in conjunction with a private branch exchange (PBX) to provide voice messaging capability to a plurality of users.
Currently, the conventional way to listen to a voice message recorded on a voice messaging system is to play the message directly from the answering machine or to dial in to the answering machine or voice messaging system to hear the message over the telephone when the user is away from the voice messaging system.
FIG. 6 illustrates a conventional voice messaging system 308 such as a digital answering machine which generally includes a processor 402 connected to a read-only memory (ROM) 418 and random-access memory (RAM) 420 which may be a dynamic random access memory (DRAM), static random access memory (SRAM), or other suitable memory. A digital signal processor (DSP) 408 is connected to a digital-to-analog (D/A) converter 410 and an analog-to-digital (A/D) converter 412. A telephone line interface 414 interfaces the voice messaging system 308 to a telephone line 114 from a telephone company central office. The DSP 408 is also connected to ROM 404 and RAM 406 which may be DRAM, SRAM, or other suitable memory. The A/D converter 412 and/or D/A converter 410 may be integrated within the DSP 408. The digital answering machine 308 may be controlled by keypad entries entered on a telephone keypad (not shown) or by dual tone, multiple frequency (DTMF) tones received from remote locations over telephone line 114.
Together with other components shown in FIG. 6, the DSP 408 converts an input analog signal to digital data, converts digital data to an output analog signal, and converts DTMF tones to digital control data.
To reduce the physical memory requirements in the digital answering machine 308, DSP 408 compresses voice message data for storage in RAM 406 and decompresses the voice message data for playback. Conventional voice compression and decompression techniques include linear predictive coding (LPC), code-excited linear predictive (CELP) coding, and vector sum excited linear predictive (VSELP) coding. These compression and decompression algorithms minimize the amount of data required to represent a voice message. The DSP 408 operates in response to a predetermined program of instructions stored in ROM 404. The DSP 408 also includes a tone generator algorithm to provide DTMF tones to the telephone line 114 and a DTMF detector algorithm to detect DTMF tones.
To store an incoming voice message in voice messaging system 308, an input voice message is conveyed over the telephone line 114 to the telephone line interface 414, which in turn conveys the incoming voice message to the A/D converter 412. The A/D converter receives the analog signal from the telephone line 114, converts the electrical signals representative of the voice message to digital data, and conveys the digital data to the DSP 408. The ROM 404 stores instructions for controlling the DSP 408 including implementation of the compression algorithm. RAM 406 receives and stores the compressed voice message. Using clock generator 416, the DSP 408 may also provide a time and date stamp with the stored digital voice message in RAM 406.
To operate the voice messaging system 308 in a remote message playback and DTMF detection mode, the user listens to a recorded message from a remote telephone 302 over telephone lines 114, 502 as shown in FIG. 7. To playback the stored voice message, the user typically inputs DTMF tones to remotely control the voice messaging system 308 such that the voice messages are played back audibly at the remote telephone 302. The A/D converter 412 and DSP 408 receive the DTMF tones representing control signals which instruct voice message playback of voice messages stored in RAM 406, under the control of the processor 402. In response to control signals from the processor 402, the DSP 408 retrieves compressed voice messages from RAM 406 and conveys digital voice message data to the D/A converter 410. D/A converter 410 converts the digital voice message data to analog signals representative of an audible output and provides the analog signals to the telephone line 114 via telephone line interface 414.
FIG. 7 shows a remote connection to the voice messaging system 308. A user calls in to the voice messaging system 308 using a remote telephone 302 over telephone line 502 and public switched telephone network (PSTN) 306. The user calls in to determine if any voice messages have been left, and if so, the user plays back the voice messages stored at the voice messaging system 308 over the telephone 302. However, the user must repeatedly call in to the voice messaging system 308, whether or not a voice message exists, to determine if a voice message does in fact exist. Needless to say, this is very inconvenient for the user. Although the user may determine that no voice messages exist without completing a call, e.g., based on the number of rings allowed by the voice messaging system 308, the user must still call in repeatedly to the voice messaging system 308 to determine whether any voice messages have been left.
The conventional digital voice messaging system 308 does not, however, automatically inform a remote user of an incoming voice message. Repeated remote access to the voice messaging system 308 from remote telephone 302 is very inconvenient for the user. Moreover, remote access requires audible playback of the message which often takes more time to hear than it would to read if the message were transcribed. Additionally, access fees and other telephone company charges may apply for the remote access to the voice messaging system 308.
A conventional answering machine which allows a user to transcribe a recorded voice message is known. For instance, as shown in FIG. 8 herein, U.S. Pat. No. 5,661,783 to Assis teaches an answering machine 700 that is connected to a printer 712 via printer cable 708 and to a computer 714 via computer cable 710. The computer 714 may also be connected to printer 712 via cable 718. A user local to the answering machine 700 may generate a written transaction of a recorded message by printing out a journal of all the caller voice messages on printer 712 and/or by displaying the caller voice messages on the computer monitor 716 and thereafter tagging selected caller voice messages which may then be printed on printer 712. While such a system allows printing of a transcribed message, it does not alleviate the need for a remote user to repeatedly call in to determine whether or not a voice message has been received.
There is a need for a voice messaging system which accumulates transcribed voice messages over time, and for a voice messaging system which automatically transmits transcribed voice messages to a remote location for reading rather than for listening.